URA3 gene expression allows yeast cells to grow on synthetic media lacking Uracil (SC-URA). Shown below are cell types having URA3 gene inserted at distinct positions of the chromosome. The ability of each cell type to grow on SC-URA in either log or stationary phase is listed on the right.
The following interpretations were made:
A. URA3 gene in cell type 1 is probably located in a heterochromatic region.
B. URA3 gene in cell type 2 is located in facultative heterochromatin.
C. URA3 gene in cell type 2 is probably located in a chromosome region silenced in log phase.
D. URA3 gene in cell type 3 is heterochromatinized in log phase.
Which one of the following options are correct interpretations?
1
A and C
2
B and D
3
A and D
4
B and C